Global Cooling Period
(Redirected from glacial period)
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An Global Cooling Period is a geological epoch associated with the presence or expansion of continental and polar ice sheets and alpine glaciers.
- AKA: Global Glaciation, Ice Age.
- Context:
- It can (typically) result in the presence or expansion of continental and polar Ice Sheets.
- It can (typically) be identified through geological evidence, such as glacial deposits and isotopic analysis of sediments.
- It can (often) lead to significant drops in global temperatures (which affects biodiversity and the distribution of life on Earth).
- …
- Example(s):
- Huronian Ice Age (~2.4 to ~2.1 BYA).
- Cryogenian Ice Age (~850 to ~635 MYA), often associated with the Snowball Earth hypothesis.
- Andean-Saharan Ice Age (~460 to ~430 MYA).
- Late Paleozoic Ice Age or Karoo Ice Age (~360 to ~260 MYA).
- Permian Ice Age (~299 to ~252 MYA), part of the Late Paleozoic Ice Age.
- Quaternary Ice Age (~2.6 MYA to present) ... Pleistocene Epoch.
- Late Ordovician Ice Age (~445 to ~440 MYA).
- Neoproterozoic Ice Age (~720 to ~635 MYA), often associated with the Snowball Earth hypothesis.
- Ediacaran Period Ice Age (~635 to ~541 MYA), following the Cryogenian Ice Age and leading into the Cambrian Period.
- Permian Ice Age (~299 to ~252 MYA), part of the Late Paleozoic Ice Age.
- …
- Counter-Example(s):
- a Global Warming Period, such as a Cretaceous Hothouse (~92 to ~66 MYA).
- See: Glaciation, Last Glacial Period, Volcanic Age, Snowball Earth.
References
2022
- (Wikipedia, 2022) ⇒ https://en.wikipedia.org/wiki/ice_age Retrieved:2022-12-9.
- An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and greenhouse periods, during which there are no glaciers on the planet. Earth is currently in the Quaternary glaciation.[1] Individual pulses of cold climate within an ice age are termed glacial periods (or, alternatively, glacials, glaciations, glacial stages, stadials, stades, or colloquially, ice ages), and intermittent warm periods within an ice age are called interglacials or interstadials.
In glaciology, ice age implies the presence of extensive ice sheets in both northern and southern hemispheres. By this definition, Earth is currently in an interglacial period—the Holocene. The amount of anthropogenic greenhouse gases emitted into Earth's oceans and atmosphere is predicted to prevent the next glacial period for the next 500,000 years, which otherwise would begin in around 50,000 years, and likely more glacial cycles after.
- An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and greenhouse periods, during which there are no glaciers on the planet. Earth is currently in the Quaternary glaciation.[1] Individual pulses of cold climate within an ice age are termed glacial periods (or, alternatively, glacials, glaciations, glacial stages, stadials, stades, or colloquially, ice ages), and intermittent warm periods within an ice age are called interglacials or interstadials.
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- https://www.history.com/topics/pre-history/ice-age
- QUOTE: ... Scientists have recorded five significant ice ages throughout the Earth’s history: the Huronian (2.4-2.1 billion years ago), Cryogenian (850-635 million years ago), Andean-Saharan (460-430 mya), Karoo (360-260 mya) and Quaternary (2.6 mya-present). Approximately a dozen major glaciations have occurred over the past 1 million years, the largest of which peaked 650,000 years ago and lasted for 50,000 years. The most recent glaciation period, often known simply as the “Ice Age,” reached peak conditions some 18,000 years ago before giving way to the interglacial Holocene epoch 11,700 years ago. ...